1. Field of the Invention
This invention relates to an improved hydrocarbon oxidation catalyst especially suitable for use with saturated hydrocarbon feeds. More particularly, it relates to improved vanadium oxide-phosphorus oxide composites. Still more particularly, it relates to the production of maleic anhydride from n-butane in a vapor phase process employing the foregoing catalyst.
2. Prior Art Description
It is known in the art that n-butane can be used as a feed for the production of maleic anhydride. n-Butane is available from petroleum refinery streams and is a relatively inexpensive feed for a maleic process. Nevertheless, there is little or no use of n-butane as a process feed for the production of maleic anyhdride. Why is this? It appears that known catalysts for the partial oxidation of n-butane are unsatisfactory. A very active catalyst is required for the oxidation. Yet this very characteristic tends to be incompatible with the requirement that the oxidation be a selective partial oxidation rather than a total oxidation to carbon oxides. That is to say, presently known catalysts for the oxidation of n-butane to maleic anhydride have, in general, relatively poor selectivities.
Representative descriptions in the art which relate to the production of maleic anhydride from n-butane include U.S. Pat. No. 3,293,268.